The present invention relates to a water closet tank for toilets. More specifically, the present invention relates to a water closet tank for toilets having an anti-condensation liner. Still more specifically, the present invention relates to a water closet tank and anti-condensation liner therefore formed entirely of plastics.
As is well known in the art, both the bowl and water closet tank of a toilet have heretofore been made of ceramics, such as china or porcelain. However, such structures have numerous known disadvantages. One major disadvantage is that they are heavy and cumbersome, thus making installation a major and expensive operation. Such structures are also expensive, which, together with the installation problems, makes both the initial or replacement cost an expensive proposition. These structures, particularly the water closet tank, are readily subject to breakage, cracking, crazing, discoloration and the buildup of sediment which cannot be removed. Accordingly, it is often necessary or desirable to replace the water closet tank. Since water closet tanks vary considerably in size, shape, capacity and relative position of the ball cock hole and flush valve hole, in some cases, and the bolts for mounting the tank to the bowl, replacement of the tank is a problem. Obviously, the tank must be made by the same manufacturer as the original, which is often impossible because of discontinued lines, and it is, therefore, necessary to replace both the tank and the bowl.
As is also obvious, ceramic articles and parts have often been replaced by synthetic plastic articles and parts. This is practical in many areas of use and is often an improvement, not only because of the lighter construction and reduction in cost but because synthetic plastics have such a myriad of "adjustable" properties that they can be essentially tailor-made for the particular use. For example, they can be either pliable or flexible or rigid and relatively non-pliable. However, the very advantages which make plastics desirable for many uses create problems if one wishes to use a synthetic plastic in the construction of a water closet tank for a toilet. It is known that any plastic has a lower flexural strength than ceramic and that rigid, high impactstrength plastics crack or break when flexed slightly. Accordingly, they are incapable of use as a material for water closet tanks, since such tanks must resist the force of a person leaning against them, unless they are made very thick or are profusely reinforced, thereby eliminating or reducing a number of the above-mentioned advantages.
It is also known in the art that all water closet tanks have a tendency to sweat or collect condensation on the exterior thereof, which eventually drips onto the floor. To overcome this problem, it has heretofore been proposed to provide an insulating liner for the tank. Such liners have been designed almost exclusively for existing ceramic tanks. Because of the previously-mentioned variations in size, shape, capacity and relative position of the ball cock hole, flush valve hole and mounting bolts, such structures are highly impractical and must generally be made for a specific brand and style of water closet tank. Even if a series of liners is manufactured to fit the most popular brands, it is still necessary to form at least the hole for the flush valve on the job in order to use one liner for more than one brand or line of tanks. This, of course, is a difficult and unenviable task for the plumber and will often be done inaccurately, resulting in a leaking liner. Further, if replacement of the tank is desired, the problems of installing the liner are added to the previously-mentioned problems of installing a new tank.
It is, therefore, an object of the present invention to provide a novel water closet tank which overcomes the previously-mentioned problems. Another object of the present invention is to provide a novel water closet tank with an insulating liner which overcomes the previously-mentioned problems. A further object of the present invention is to provide a novel water closet tank and such a tank with an insulating liner which is practical, inexpensive, durable, simple in construction, easily installed, lightweight, of attractive design and/or adaptable to installation on a wide variety of standard toilet bowls. Yet another object of the present invention is to provide a novel water closet tank of thin, rugged, high-impact synthetic plastic which will withstand both internal pressure (water pressure) and external pressure (a person leaning against it). Another object of the present invention is to provide a novel water closet tank having clean exterior lines unencumbered by extensions or protrusions which detract from the aesthetic appearance, make installation difficult or prevent a snug fit of an existing bowl. A further object of the present invention is to provide a rigid, high-impact strength water closet tank with a relatively more pliable liner spaced from the interior of the tank to provide an insulating air space therebetween. A further object of the present invention is to provide a water closet tank with an insulating liner of the character just described in which the water pressure in the liner forces the upper edges of the liner against the tank to form an air-tight seal between the two. Another and further object of the present invention is to provide a water closet tank with a liner spaced from the inside of the tank to form an insulating air space in which a tight, leak-proof seal can be formed when the ball cock assembly and flush valve assembly are installed and which installation binds the liner to the tank. Still another object of the present invention is to provide a novel water closet tank with an interlocking cover which reinforces and prevents flexure of the side walls of the tank. Another and further object of the present invention is to provide a novel water closet tank with an insulating liner which utilizes a significantly smaller volume of water.
These and other objects and advantages of the present invention will be apparent from the following description.